Check valve for liquid-fuel tanks



Feb. 10. 1925. 1,525,861

J; B. FRANKLIN GIIECK VALVE FOR LIQUID FUEL TANKS Filed Dec. 27. 1922 $7Quota mg:

Patented Feb. ltd, 1925.

JOHN B. FR-ANKLEN, OFPARKERTON,WYQMING.

CHECK VALVE FOR LIQUID-FUEL TANKS.

Application filed December 27, 1922. Serial No. 603,245.

T 0 all whom it may concern:

Be it known that 1, JOHN B. FRANKLIN, citizen of the United States,residing at Parkerton, in the county of Converse and State oi Wyoming,have invented certain new and useful Improvements in Check Valves forLiquid-Fuel Tanks,of which the following is a specification.

Ely invention relates to improvements in check valves used in the airvents of liquid fuel tanks and more particularly to a check valve foruse in the gasoline tanks of cars.

The caps or covers for the filling openings in such tanks are usuallyprovided with a small vent for admitting air into the tank to replacethe drained of? gasoline during the running of the automobile.

It is a well known fact that a considerable amount of gasoline splashesout through these vents and collects on the top of the tank. Thisgasoline gradually evaporates and spreads a disagreeable odor, not tomention the danger of fire in case a match or other open light is heldnear the tank. Aside from the splashing out of the gasoline through thisvent,'the gases collecting in the top of the tank will escape throughthe vent and provide source of danger from fire, as well as producing anunpleasant odor.

One object of the present invention is to obviate this danger of fireand the spreading of the odor from the evaporated gasoline by theprovision of a suitable check valve to be inserted in the vent.

The provision of this check valve also tends to save gasoline, which isotherwise lost through the vent, and the advantages of having a checkvalve of this character for gasoline tanks are accordingly theprevention of fire and the saving of gasoline.

In the accompanying drawing, one embodiment is illustrated, and

Figure 1 shows a fragmentary perspective view of a gasoline tank with mycheck valve in position;

Figure 2 is a vertical axial section of the check valve, together withthe related parts of the tank; and

Figure 3 is a horizontal section along line 3-8 of Figure 2.

In the drawing reference numeral 10 represents a gasoline tank of theusual construction, provided with a cylindrical portion 11, having afilling opening 12. This cylindrical portion has external threads 18 fora cover 11, fitting over the same and having correspondingthreads forclosing the opening. In order to receive the check valve 15, the vent16in the center of the cover 1a is threaded to correspond with thethreads on a shank 1'? formed at the lower ene 01": the barrel 18 of thecheckvalve 15. The upper end of the barrel 18 has a threaded portion 19,which is of smaller diameter than the barrel itself and adapted toengage the correspondingly threaded lower end or a cap 20. The outsidediameters of the cap 20 and the barrel 18 coincide, so that when the capis screwed down upon the barrel, they provide a smooth surface. The topof the cap 20 is rounded and a small vent 21 is drilled axially throughthe cap 20 and in alinement therewith, the lower vent 22 being drilledthrough the barrel 18 and its shank 17.

An enlarged chamber 23 is formed at the inner ends of the vents in thebarrel 18 and the cap 20, and in this chamber is inserted a small valveplunger 24, which fits loosely in the chamber, but is adapted to beseated against the upper end of the chamber in the cap 20, so as toclose the vent 21 when in this position. The plunger has a small wart orlug 25 on the under side adapted to engage the upper end or" acompression spring 26, seated against the plunger 2%. The lower end ofthe spring 26 rests on the bottom of the chamber 23. In this manner,when the plunger 24 is pressed upwardly by the spring 26 to close thevent 21, with the parts assembled, the strength of the spring is soselected that, when the internal pressure in the tank becomes less thanatmospheric, the plunger will descend slightly in the chamber, therebypermitting atmospheric air to enter the vent 21 and pass by the plunger2 1 through the lower vent 22 into the tank 10.

It will now be evident that, when the tank is partly or completely fulland the cover 1 1 screwed down over the filling opening 12, and with thecheck valve 15 in position in the cover, there is no chance for escapeof gases collected in the tank through the vent 21, unless the pressurewithin the tank is less than the pressure without. Accordingly, as longas the automobile is standing still there will be no escape of gasesthrough this vent.

When the car is set in motion and gasoline is fed from the tank into theengine, a suction will be set up within the tank which gradually willovercome the strength of the spring 26 and lower the plunger 24: when acertain quantity of atmospheric air will enter the vent 21 to replacethe drained ofl' gasoline. The only chance for gasoline to splashthrough the vent is prevented by the intercepting plunger 24, so that,should any gasoline run up through the vent 22 into the chamber 23, itwill return into the tank as there is no chance for it to pass theplunger 24.

In this manner all danger of fire is prevented; no bad odor will befound around the tank and a saving of gasoline will be the consequence.

Having thus described the invention what is claimed as new is:

A check valve of the class described com tending shank and a downwardlyextending shank, said downwardly extending shank being firmly secured inthe filling cover of a fluid tank, a cap for said barrel having threadedengagement with said upwardly extending shank, a smooth bored chamberbeing formed in said valve extending with one end into the barrel andwith the other end into the cap, vents being provided in said barrel andsaid cap connecting said chamber with the interior of the tank and withthe atmosphere respectively, a fiat faced valve seat being formed aroundthe vent in the cap, a flat faced, cylindrical plunger slidab-lyarranged in said chamber, and a yieldable element tending to press theplunger over the vent against the flat faced seat to close the same.

In testimony whereof I affix my signa ture.

JOHN B. FRANKLIN. [1,. s]

